Science Saturday: The gene-editing tool CRISPR, explained

August 25, 2018

With a new gene-editing tool called CRISPR, scientists have the power to tweak the genomes of plants, animals and even humans. Read on to learn what CRISPR is, how it works and why it could change your life.

What It Is

CRISPR (pronounced “crisper”) stands for Clustered Regularly Interspaced Short Palindromic Repeats – repetitive fragments of DNA that bacteria use to defend themselves against invading viruses. Viruses can infect bacteria, just like they can infect you or me. When we develop a viral infection, our immune system produces antibodies against the virus so we can quickly respond the next time we are threatened.

For many bacteria, CRISPR serves as a kind of immune system. When infected, the bacteria gather pieces of the viral code and tuck them into their own genomes for safekeeping. These sequences serve as a kind of immunological memory, providing the bacteria with a molecular fingerprint of the viruses that infected them. If that same virus shows up again, the bacteria recognizes it and unleashes a DNA-cutting protein called Cas9 to chop up the invader’s genetic code. That’s why many people refer to the technology as CRISPR/Cas9. Read the rest of the article on Discovery's Edge.___________________________________________